In order to whitelist the Addemar sender ip ranges, you can follow one of these steps:

• If your mailserver allows whitelisting based on spf records, you can include our spf record.
  Our main spf record that you need to include is: spf.addemar.com
  
  More information about spf can be found here.
  
  
• If your mailserver does not allow whitelisting based on spf record, you can add our ip ranges to whitelist all mails coming from Addemar.
  
  A simple way to extract our ips from our spf record (spf.addemar.com) is with an online tool like:
  https://mxtoolbox.com/SuperTool.aspx?action=spf%3aspf.addemar.com&run=toolpage

When whitelisting, we recommend doing this by spf record over whitelisting fixed ip ranges!

By using the spf record, you will always be up to date with our ranges. As these IP adresses can change in order to maximize our deliverability.

Tip: DKIM authentication is another great way to improve the overall deliveriablity of your emails.
More information about DKIM can be found here.